/Engine/Source/Runtime/Core/Public/HAL/ThreadSingleton.h
an instance of a singleton for the current thread.
static [FTlsAutoCleanup](API\Runtime\Core\HAL\FTlsAutoCleanup) * Get ( [TFunctionRef](API\Runtime\Core\GenericPlatform\TFunctionRef)< [FTlsAutoCleanup](API\Runtime\Core\HAL\FTlsAutoCleanup) *()> CreateInstance, uint32 & TlsSlot )